1. Field of the Invention
The present invention relates to an electro-developing type video camera using an electro-developing recording medium. More particularly, the present invention is directed to electronically and directly recording and developing, as a visible image, an optical image obtained through a photographing optical system, and for controlling the recording operation of the recording medium.
2. Description of the Related Art
Conventionally, there is known a recording medium which electronically develops an optical image formed thereon through a photographing optical system.
Such a recording medium is a combination of an electrostatic information recording medium and an electric charge keeping medium. In the electro-developing recording medium, the electrostatic information recording medium has a photoconducting layer and an inorganic oxide material layer. The electric charge keeping medium has a liquid crystal display. When the electrostatic information recording medium is exposed while an electric voltage is applied to both the electrostatic information recording medium and the electric charge keeping medium, an electric charge in accordance with the amount of incident light is generated in the electrostatic information recording medium.
There is an electro-developing type video camera, which has a color separation unit comprising red (R), green (G), and blue (B) color filter elements, and a recording medium unit comprising recording mediums. While photographing an object, the color separation unit and the recording medium unit are moved in synchronization with each other, so that light passing through a photographing optical system passes through R, G and B color filter elements. The color components (R, G, B) are separated, and optical images corresponding to each color component are recorded on the recording mediums, respectively. In this type of electro-developing type video camera, optical image data corresponding to each color component is read by, for example, scanning the optical images with a line sensor. The color image of the object is made by synthesizing the optical image data.
The optical image data can be synthesized by positioning each optical image by sight. However, the efficiency of synthesization by sight is low, because high skill is necessary to position the optical image data. Accordingly, it is very difficult to get an extremely precise object image.
As disclosed in Japanese Unexamined Patent Publication No. HEI 5-2280 and U.S. Pat. No. 5,424,156, there is known a photographic material which is directly and electronically developed so that a developed visible image can be immediately obtained. In this specification, such a recording medium is referred to as an electro-developing recording medium, and an electronic still camera using the electro-developing recording medium is referred to as an electro-developing type camera.
An image recorded on the electro-developing recording medium is hard to see, and therefore, it is difficult to recognize at a glance whether the recording medium has been recorded.
On the other hand, the electro-developing recording medium may have a plurality of recording areas, where the three primary color images corresponding to the object image can be recorded. These color images are superimposed on one another to form an image having a natural color.